Electric fuel pump



June 22, 1937. E. F. WEBB 5 ELECTRIQ FUEL PUMP Original Filed. 001:. 28,1933 .57 so WWI I; 8 7 56 as 1 15.3.

36 v 11 30 a4 3% 2.5:; Q 2, n 38* 1/20 as 42 -i I' III INVENTOR. EDMONDE WEBB.

Patented June 22, 1937 UNITED STATES PATENT OFFHCE ELECTRIC FUEL PUMPEdmond F. Webb, Royal Oak, Mich., assignor to Chrysler Corporation,Detroit, Mich., a corporation of Delaware 5 Claims.

This invention relates to an improved fuel pumping system for internal'combustion engines and particularly to an electrically energized deviceof this character.

The main objects of the invention are to provide an electric fuelpumping system. for feeding fuels under pressure from a fuel tank to thecarburetor or other fuel delivery means of an internal combustionengine; to provide a magnetically operable pump unit in a system of thiskind having a solenoid circuit which extends into the fuel tank; toprovide a circuit of this kind which has completely closed portionsextending into the fuel tank and located in the vicinity thereof, saidcompletely closed portions being absolutely devoid of make and breakdevices and other spark forming element; to provide a pump unit whichmay be safely located in the fuel tank where it is free from vapor lockwhich occurs when the fuel pump is mounted in close prox imity to anengine and subjected to the heat radiated therefrom, without the hazardof ignition of fuel or fuel vapor in or around the tank; and

to provide a device at a remote location from the 7 fuel tank forintermittently energizing the solenoid of the pump unit.

Other objects of the invention are to provide an improved device forintermittently energizing the solenoid of an electric fuel pumping unit;to provide a device of this character which may be constructed andarranged to be operated by any conventionally located rotative part ofan engine, such as the crank shaft, the cam shaft or distributor shaftthereof; to provide a commutator which is adapted to cause the fueldisplacing element of the pump unit to perform more strokes perrevolution of the commutator rotor at cranking speed of the engine thanduring idling operation thereof, and substantially fewer strokes 40 perrevolution of the commutator rotor during operation of the engine atnormal running speeds; and to provide a device of this character whichWill deliver a greater quantity of fuel per revolution of an. enginecrank shaft during en- 45 gine cranking operations than during normalrunning operations.

An illustrative embodiment of the invention is shown in the accompanyingdrawing, wherein:

Fig. l is a diagrammatic end elevational view of an engine, and a sideelevational view of a fuel tank equipped with my improved electric fuelpumping system.

Fig. 2 is an enlarged transverse section of the fuel pumping unit takenon the line lI-II of 55 Fig. 1.

Fig. 3 is a transverse sectional view taken on the line IIIIII of Fig.1, and illustrating somewhat diagrammatically the commutator stator androtor of the improved fuel pumping system.

Fig. 4 is a transverse sectional view of the pumping unit taken on theline IVIV of Fig. 2.

In the form shown, the improved fuel supplying system includes a pumpingunit It) which is disposed in a fuel tank l! of the type conventionallyprovided on motor vehicles, and located 10 at the rear end thereof. Thepumping unit includes a tubuluar member l2 which is provided at itsupper end with a frusto-conical portion l3 having a radial flange I4disposed between gaskets I5 mounted on the top surface of the fuel 15tank I! and surrounding an opening it in the latter. The lower end ofthe tubular member l2 is also provided with a frusto-conical portionhaving a radialflange E8 to which a cylindrical casing is attached bybolts 2|. The casing 20 20 includes a lower cup shaped element 22 havinga disc 23 disposed over its open extremity, the disc 23 and cup shapedsection 22 being secured together by the bolts 2|. A gasket 24 isprovided between the. radial flange |8 of the tubular mem- 25 her l2 andthe disc 23 and a gasket 25 is disposed between the latter disc and thecup shaped section 22 of the casing 20 for forming liquid tight sealsbetween the convenable parts of the structure. A valve housing 26 havingan inlet opening 21 is secured to the lower extremity of the cylindricalcasing 28 by the bolts 2|.

Concentrically located in. the cylindrical casing 20 is a cylindercomprising a metal sleeve 28 having an opening 29 in its upper extremitysurrounded by an inwardly extending flange 39. The lower end of thecylinder 28 is provided with an opening 3| which communicates with theinlet opening 21 of the valve housing 26 through a plurality of passages32 formed in the lower wall of the cup shaped section 22 of the casing20. The inlet opening 21 of the valve housing 26 is normally closed by adisc valve 33 which is yieldably held upon its seat by a coil spring 3bearing between the disc valve and the lower extremity of the cup shapedsection 22 of the casing 29.

Reciprocably mounted in the cylinder 28 is a piston 35 which preferablycomprises iron or other magnetically attractable metal. The piston 35has a substantially hollow interior and it 5 is provided with a headportion 36 having outlet apertures 31. The outlet apertures 3communicate with the interior of the piston and with an inlet opening 38to the interior of the piston which is normally closed by a disc valve39. The

disc valve as is yieldably held upon its seat by a spring 4E bearingbetween the valve and the internal side of the head 35 of the piston.

A spring ti normally urges and yieldably holds the piston 35 at theupper end of the cylinder 28, and a solenoid d2 surrounding the cylinder28 and located between the latter and the peripheral wall of the casing2c is provided for intermittently urging the piston 35 downwardlyagainst the action of the spring ti. Each upward stroke of the piston 35opens the valve 33 and draws fuel into the interior of the cylinder 28,and each downward stroke of the piston forces the fuel trapped betweenthe latter and the valve 33 upwardly through the opening 38 past thevalve 3% and through the outlet apertures 3?. Fuel is in this mannerdelivered under pressure-to the tubular member l2 from which it isconveyed by a conduit 55 to the fuel reservoir 63 of a carburetor i iwhich is included in the fuel mixture supply system 38 of an internalcombustion engine 59. The rear end of the conduit Ell is provided with afitting M which is threaded in an opening 52 of a disc shaped cap 53disposed over the opening it in the fuel tank, and normally secured tothe latter by bolts 56.

The solenoid i2 is electrically connected in a circuit 55 leading fromthe solenoid to suitable make and break apparatus by which the solenoidis intermittently energized. The circuit 55 includes a pair of leadwires 56 and 5'! which are integrally connected with the Winding of thesolenoid and permanently secured to terminals 58 and 59 mounted on thecap 53 and electrically insulated therefrom by insulating sleeves iiiand ti. The portion of the circuit 55 which is disposed in the tank andthe portions thereof located in the vicinity of the tank are permanentlyclosed. One terminal of a battery 62, or other source of power, isdirectly connected to the terminal 58 of the pump unit, and the otherter minal of the battery is directly connected with the make and breakapparatus. The ternunal 58 of the pump unit is also connected to themake and break apparatus.

The made and break apparatus illustrated in the drawing includes acommutator having a stator 63 and a rotor 64. The rotor may be driven byany conventionally accessible rotative part of the engine ll but it ispreferably operatively connected with some member of the engine whichrotates either in unison with the engine crank shaft or at some speedproportional to the speed of rotation of the engine crank shaft.

One operative connection between the crank shaft of the engine and therotor 64 of the commutator is illustrated in Fig. 1, wherein the enginecrank shaft 55 is provided with a pinion 66 which is connected by achain all with a gear 78 mounted on the engine timing shaft l9. A pinionsecured to the timing shaft is is meshed with a Worm gear 8% carried bythe distributor shaft 82 of the engine. The shaft 82 operates theconventional distributor mechanism of the engine ignition system andalso operates the rotor E i of the commutator of the fuel pumping systemin timed relation to the crank shaft. The rotor of this commutator may,it is recognized, be driven by any rotative part of the engine. For thepurpose of convenience of illustration, and in order to disclose oneeconomical manner for operating the commutator rotor, the latter hasbeen combined With the distributor so that the rotor of the distributorand the rotor of the commutator may be driven by the same shaft.

The rotor 64 of the commutator is provided with a contact element 83which is adapted to successively engage a plurality of circumferentiallyarranged contact elements formed on the stator 63. The stator may beprovided with any desired number of contact elements which arepreferably asymmetrically arranged and of dif ferent lengths, theconstruction and arrangement of the contact elements of the stator beingsuch that at low speed rotation of the rotor it the solenoid d2 will beenergized throughout a greater number of periods of sufficient durationto cause the piston to perform more strokes per rotation of the rotorthan during high speed operation of the latter. In the form shown, thisis accomplished by providing the stator with three relatively longcontact elements which are located in close proximity to each other, andthree comparatively short contact elements 85 which arecircumferentially spaced at greater distances apart. The exposedportions of the contact elements are separated from each other bysuitable dielectric material. The relative lengths of the contactmembers and the distances therebetween are preferably predetermined sothat, during rotation of the rotor at cranking speeds of the engine,each contact element will cause the solenoid d2 to be energized longenough to permit the pis ton to be moved to the lower end portion of thecylinder 28 and to thereafter be projected up- Wardly so as to performone complete discharge stroke for each contact element of the rotor. Theconstruction and arrangement of the contact elements of the stator issuch that at idling speeds of the engine, the three closely adjacentcontact elements fi l will produce only one effective stroke ofthepiston and each contact element will cause the piston to perform onepartial stroke respectively. At normal running speeds of the engine,however, only one stroke of the piston is produced during each rotationof the rotor 54, for the periods of energization occurring while thecontact 83 of the rotor is in engagement with the short contacts 85 ofthe stator are of insufficient duration to permit the solenoid toovercome the action of the spring il and the inertia of the piston, and,therefore, the piston is not moved from its uppermost position shown inFig. 2. The duration of the periods of interruption of energization ofthe solenoid brought about by the dielectric material E6 between therelatively long contacts 34 is insuflicient to permit the spring ii tourge the piston 35 upwardly, as contact between the element 83 of therotor and successive elements 8d of the stator is broken, and thereforethe piston remains in its lowermost position substantially from the timethe contact 83 engages the first of the series of three contact elements84 until the contact element 83 becomes disengaged from the last of saidseries of contact elements. In operation of the engine at its normalrunning speed, only one effective pumping stroke of the piston occurs,while during operation of the engine at cranking speeds sixsubstantially full strokes of the piston take place. At idling speedsthree substantially full strokes and three partial strokes of the pistonoccur. In this manner the system is conditioned to supply the requiredamount of fuel to the carburetor at the diverse speeds at which it isoperated.

By locating the pump unit in the fuel tank which is conventionallydisposed remote from the engine and engine compartment of a vehicle,

vapor locking of the pump unit is effectively guarded against. This canbe accomplished with the improved vehicle pumping system without theaccompanying hazard of fire or explosion resulting from ignition of thefuel or fuel vapor in or around the tank, for all portions of thesolenoid circuit located in the tank and all those portions thereoflocated in the vicinity of the tank are permanently closed. The make andbreak apparatus is safely located in the engine compartment of thevehicle at a considerable distance from the fuel tank so that there isno danger of ignition of the fuel by the sparks or arcs which may occurduring engagement and disengagement of the contacts of the rotor withthe contacts of the stator of the commutator.

Although but one specific embodiment of the invention is herein shownand described, it will be understood that various changes in the size,shape, and arrangement of parts may be made without departing from thespirit of my invention, and it is not my intention to limit its scopeother than by the terms of the appended claims.

What I claim is:

1. In a vehicle having an internal combustion engine provided with afuel system including fuel feeding means adjacent said engine and a fuelsupply tank remote therefrom; apparatus for supplying fuel underpressure from said fuel tank to said fuel feeding means including a pumpunit in said fuel tank having a magnetically op erable fuel displacingelement and an electromagnetic member for operating said element, acommutator remote from said fuel tank having a stator member and havinga rotor member operatively connected with a rotative part of saidengine, one of said members having a plurality of contact elements forengaging the other member, some of said contact elements being ofdifferent lengths and asymmetrically arranged to cause said fueldisplacing element to perform one effective stroke per contact elementduring each revolution of said rotor member at cranking speeds ofsaid-engine and to cause said fuel dis placing element to perform lessthan one effective stroke per contact element during each revolution ofsaid rotor member at normal running speeds of said engine, and a circuitincluding a source of electric power and connecting saidelectro-magnetic member and said contact elements, all portions of saidcircuit within said fuel tank and in the vicinity thereof beingpermanently closed.

2. In a vehicle having an internal combustion engine provided with afuel system including fuel feeding means adjacent said engine and a fuelsupply tank remote therefrom; apparatus for supplying fuel underpressure from said fuel tank to said fuel feeding means including a pumpunit in said fuel tank having a magnetically operable fuel displacingelement and a solenoid for operating said element, a commutator having astator member and having a rotor member operatively connected with arotative part of said engine, one of said members having a plurality ofcontact elements for engaging the other member, some of said contactelements being of different lengths and asymmetrically arranged to causesaid fuel displacing element to perform one substantially full strokeper contact element during each revolution of said rotor member atcranking speeds of said engine and less than one full stroke per contactelement during each revolution of said rotor member at idling speeds ofsaid engine and only one effective stroke per contact element duringeach revolution of said rotor at normal running speeds of said engine,and a circuit including a source of electric power and connecting saidsolenoid and said contact elements.

3. In an internal combustion engine; a pumping apparatus including areceptacle, a magnetically operable fluid displacing element in saidreceptacle, resilient means for normally urging said element in onedirection, a solenoid for moving said element in an opposite directionagainst the action of said means, and a commutator including a statormember and a rotor member, means for driving said rotor member in timedrelation with said engine, one of said members having a set of widelyspaced comparatively short contact elements and a second set ofrelatively longer contact elements disposed in close proximity to eachother, said contact elements being constructed and arranged to causesaid fluid displacing element to perform one stroke per contact elementduring each rotation of said stator at a speed within a predeterminedrange and to cause said fluid displacing element to perform less thanone stroke per contact element during each rotation of said rotor atspeeds above said predetermined range.

4. In an internal combustion engine; a pumping apparatus including areceptacle, a magnetically operable fuel displacing element in saidreceptacle, means for operating said element including anelectro-magnetic member, means for driving said rotor member in timedrelation with said engine, a commutator including a stator member and arotor member, one of said members having a set of widely spacedcomparatively short contact elements and a second set of relativelylonger contact elements disposed in close proximity to each other, saidcontact elements being so constructed and arranged as to establish ahigher ratio of strokes per contact element at low speed operation ofsaid rotor member than at operation thereof at normal running speeds.

5. In an internal combustion engine, a pumping apparatus including areceptacle, a magnetically operable fuel displacing element in saidreceptacle, means for operating said element including anelectro-magnetic member, a commutator including a stator member and arotor member, means for driving said rotor member in timed relation withsaid engine, one of said members having contact elements thereon andsome of said contact elements being of different effective lengths andbeing asymmetrically arranged so as to establish a higher ratio ofstrokes of said fuel displacing element per contact element during lowspeed operation of said rotor member than during operation thereof atnormal running speeds,

EDMOND F. WEBB.

